Which one?

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When one has one of those discussions and we all have had them, We might as well be in the woods talking to trees.

Where is it said honey do list are unilatteral? I mean I could never figure out when to paint a room? or how to alot my weekend time? When is it my fault the boiler is not making enough hot water? I mean my wife's car's breaks squeak. Yeah I drove it 500 of the 50,000 miles.
 
Shane said:
The EPA numbers you can count on. The efficiency numbers are close too. Combustion Efficiency=energy produced during combustion/amount of energy available before combustion. Heat Transfer Efficiency=percentage of heat generated by combustion actually transferred to the room. Overall efficiency=useful energy output/fuel energy input. I don't see how they can really fudge those numbers. The burn times are a matter of interpretation.

I thought the EPA tests were more concerned with emissions and not efficiency? If they were more into BTU's wouldn't they fill the firebox with hardwood instead of a small pine charge? I don't see how the EPA test can be close to real world burning.
 
How about safety? Between an EPA stove and an EPA insert, which is safer? I'm sure the official line is that they're both safe when properly installed, blah blah blah. But in the real world which turns out to be generally safer, i.e. per years of operation?
 
The EPA tests are related to efficiency as those emmissions are unburned unused energy. The more emmissions the less combustion efficiency, the less combustion efficiency the less overall efficiency.
 
I represent efficieny the same way shane, on the sales floor i tell customers to look at GPH instead of what percent the manufacture states that there getting. I think its funny that there is no reg on hight for the flue probe thermometer that they test with. what happens when company a puts there probe at 15' and company b puts theres at 20'. Company b always will show a better efficiency. what a joke.
 
MountainStoveGuy said:
I represent efficieny the same way shane, on the sales floor i tell customers to look at GPH instead of what percent the manufacture states that there getting. I think its funny that there is no reg on hight for the flue probe thermometer that they test with. what happens when company a puts there probe at 15' and company b puts theres at 20'. Company b always will show a better efficiency. what a joke.

That brings up something I have wanted to ask for for a long time here. I was hoping Craig would post it some day.

What are the steps in the EPA test procedure? I have tried to find them and they appear to be some deep dark secret, except for the part about using pine for the burns. Stuff like does the EPA take a manual and run the stove like Harry Homeowner or does the manufacturer do a show for them etc. etc.?
 
I believe they take one pound of doug fir, and burn it for one hour. I might be mistaken on the amount of wood and time, but its a set weight at a set time. Have you ever looked at the fine print on all the epa tags on stoves? they all say "not tested for efficiency, this number represents a average of non- catalitic stoves" the data is the same on all of the stoves but the manufacturs listing says something different when it comes to grams per hour. But the grams per hour on the epa hang tag are all the same. confusing.
Or i could be reading the grams per hour wrong on the hang tag. the scale is so vauge its worthless anyway.
 
EPA Wood Stove Certification Data Sheet

The testing of wood stoves for EPA certification conducted by Intertek is done following EPA Methods 28 and 5G-3. Below is a short description of terms and procedures.

>> The emissions rate is the weight of particulates emitted into the flue gas over a given period.

>> The weighted average emission rate balances the emissions according to the burn rate of the wood.

>> Catalytic stoves must have a weighed emissions rate of 4.1 grams per hour or less, while non-catalytic stoves must have a weighted emission rate of 7.5 grams per hour.

>> The stove is tested at 4 different burn rates:
>> Category 1 = Less than .8 kg/hr; Less than 1 kg/hr if the control is in the full closed position
(Dry wood burn rates = amount of wood minus the moisture content divided by time burned)
>> Category 2 = .8 kg/hr – 1.25 kg/hr
>> Category 3 = 1.25 kg – 1.9 kg/hr
>> Category 4 = 1.9 kg/hr or more (all controls on the unit must be at its highest burn rate position)

>> The fan is run on high for all runs unless specified differently in the owner’s manual.

>> Optional fans require another run category with the fan off.

>> The unit is placed on a platform scale. Single wall pipe is installed to 8’6”± 6” above the scale platform with insulated chimney extending it to 15’± 1’.

>> The firebox volume is calculated using your production drawings. The calculated volume multiplied by 7 is the test fuel load weight (± 10%). Air-dried Douglas Fir with moisture content between 19 and 25% (dry basis) is cut to 5/6 the largest length of the firebox.

>> If the firebox volume is:
>> <1.5 cu. ft. use all 2x4’s
>> 1.5 to 3 cu. ft. use half the weight in 2x4’s and the rest 4x4’s
>> >3 cu. ft. use all 4x4’s

>> Douglas Fir spacers (3/4” x 1-1/2” x 5”) are placed at the ends (top and bottom) of test load pieces.

>> A fire is started with kindling and paper. A preload consisting of 2x4’s at least 1/3 the length of the test load pieces and roughly the weight of the test load is then placed in the stove. The air controls may be adjusted, the door open or the coal bed raked during the preburn. At least 1 hour before the test load is inserted the air controls may not be adjusted. The coal bed may be stirred at any time until 15 minutes before the test run. During the last 15 minutes of the preburn the door can only be open for 1 minute to rake the coal bed.

>> The test load is inserted when the weight of preload in the stove is 20 to 25% of the test load weight. The scale is adjusted so that the weight is at 0 pounds. The test load is then loaded in the stove within 1 minute. During the first 5 minutes of the test the air controls, fan, and door may be adjusted according to the manufacturers written instructions. After 5 minutes nothing can be adjusted until the end of the test is reached. This occurs when the weight of the wood has returned to 0 pounds. (One stir is allowed after 60% of the test load has burned and the test load weight has not changed .1 pound or 1% of the test load over a 10-minute period, but the door may be open only for 15 seconds during the stir).

>> Continuously during the test a portion of the flue gas is pulled through a filter collection system. Every 10 minutes a reading is taken of CO, CO2, O2, stove temperatures (the average of the five firebox surface temperatures may only vary ± 125 degrees between the start and finish of the test), gas sample rates, tunnel velocity, stack temperature, tunnel temperatures and dry gas meter readings. These readings provide the proportional flow rate between the tunnel and the collection system. This data is also used for the calculation of the efficiency of the unit following CSA Standard B415. The final grams per hour are calculated after weighing the filters.

This info is taken from Warnock Hersey web site None was edited by me
 
MountainStoveGuy said:
I believe they take one pound of doug fir, and burn it for one hour. I might be mistaken on the amount of wood and time, but its a set weight at a set time. But the grams per hour on the epa hang tag are all the same. confusing.
Or i could be reading the grams per hour wrong on the hang tag. the scale is so vauge its worthless anyway.

This conversation went on about 8 years ago here and the answer is still probably the same. Or answers....plural.

My opinion is this - perhaps some manufacturers will step in:

The hang tags and tests mean little because:

a. Oven dried fir firebrands so not burn like 20% moisture oak.
b. Many stoves are designed with passing the tests in mind, sometimes even at the expense or real world use.
c. Operator, chimney, fuel and altitude variables still exist.
d. EPA does not test stoves. In fact, test labs usually do not test stoves. MANUFACTURERS test stoves, usually in their own labs and present witness and sworn results to EPA or test labs.
e. These tests do not take things like insert heat loss up the chimney, and fireplaces built on exterior walls into account.

Taken all together, one cannot use EPA efficiency as a valid means of comparing product types or even various models.

So, what to do? Well, given that most people burn a cord or two a year for entertainment and perhaps backup heat if power goes out, there would be little difference between a 60% and a 70%+ rated stove....even if comparisons were accurate.

However, those who are serious wood junkies should look hard at freestanding stoves with interior chimneys and exposed pipe....or at efficient central heaters (somewhat lacking in selection).

When all is said and done, there is only one choice (wait a minute, I have to check if my sponsors paid up yet) - OK, yes, I was saying the one choice is....... :p

Just my opinion....
 
Craig/ MO this question has surfaced time and time again. Any way to save or refference this epa proceedure. Would it be better to start a new post with Epa testing proceedures so shearches would find it?

Boy did we hyjack this thread Most if not all of what Craig says I agree with I mean Manufactures claims do not make sense.

Given that then we can start comparing firebox sizes But that is not all that accurate either. Thermal mass of the actual stove must be considered too. then the properties of its materials Cast Iron / steel plate and cast iron/ soapstone. Then there is the actual radiant surface area and some stoves are combination of radiation /convection

The everburn is a marketing way, reguritating existing technology. The down draft secondary air burn cycle was already present in these stoves models, for many years prior. True they may have tweaked the technology to improve the chamber and secondary air supply. Is it better than the secondary air tubs other manufactures imploy?
 
Webmaster said:
The hang tags and tests mean little because:
a. Oven dried fir firebrands so not burn like 20% moisture oak.
b. Many stoves are designed with passing the tests in mind, sometimes even at the expense or real world use.
c. Operator, chimney, fuel and altitude variables still exist.
<snip>

In general, I don't disagree with what you're written. But I will add my experience with 5 stoves installed this past burning season (three in my home, two in friends' homes).

For those of us 'condemned' to burn softwoods, the test reults for heat output range as printed on the EPA tag correlate quite well with the stove's performance we experienced - much better than manufacturer's claims and recommendations. In fact, of these five, the two stoves that performed the worst were the ones that had the greatest discrepancy between the manufacturers advertised max. heat output and the EPA test result. It can vary by a factor of two or more!

So, for softwood burners, I say, pay attention to the EPA tag results.

A list with specs of all stoves certified thru June 5005 at: http://www.state.nj.us/dep/airworkgroups/docs/certifiedwood.pdf
 
the only thing unique on a epa hang tag is the grams per hour rating. The efficiency is the same on all the tags.
 
I disagree with efficiency numbers not being something to count on or atleast draw a baseline from. It's a consistent test. Of course there are real world variables such as user error, moisture content and species of wood etc. but for every stove to pass a baseline test that is the same to me gives somewhat of a apple to apple comparison. It seems there is this perception that stove companies are screwing customers over. I don't think so, when they claim an efficiency or btu output number they're representing what their stove can do under optimal conditions. But there is nothing wrong with that, I would do the same thing. I mean if we can't use btu inputs, overall efficiency ratings and epa numbers what do you use to compare? Do you decide on which one looks prettiest? Do you do what Jimbob tells you to do and buy what ever stove he's recommended? Firebox size means chit, you still have to factor heat transfer and combustion efficiency. Firebox size can be 5 cu.ft. and only have a 40% combustion efficiency on one stove and a 90% on another. There are laws against false advertising and I don't think it's in the best interest of any stove company to misrepresent their units.
 
yea, i over looked that. In my hands i have to tags. The Hearthstone Mansfield, there 80,000/3.0 cubic foot box, EPA rated at 45,300 and the Quadradire 3100 50,000 btu/2.2 cubic foot firebox epa rated at 47,000 btu's. I dont beleive the EPA tag is remotly accurate for the mansfield, the quadrafire seems close. This is probably due to the test conditions, i think steel would fair better in the epa test then soapstone, if i had to guess.
 
T
here are laws against false advertising and I don’t think it’s in the best interest of any stove company to misrepresent their units.
Except for Vogelzang

Prime example of false or miss leading advertising, "Meets or exceeds EPA requirements."

It then tells you in the installation owner’s manual it is EPA exempt.
 
Shane, i think you can compare apples to apples pretty well when you take modern non cat or cat stoves and compare firebox size to get a good baseline for what they can do. Heat outputs from manufacturs are all over the board. I think most of the high end non cat and cat stove are within 10% either way. So when comparing lopi to quad, vermont castings to jotul, i feel that you can rely on firebox size to be a good indicator that your looking at the same heating class stove, even thouhg one manufacture states that there 2.5 cf firebox is 50k btu. and the other manufacture states that there 2.5 cf firebox is 80k btu. I dont think that there burn efficiency is that much different, just the way the manufacture tested it differs. And the epa tags dont even address burn efficiency.
 
A firebox size comparison in conjunction with overall efficiency would to me offer a great comparison. What do you guys think of this idea for getting a true apples to apples comparison. My thought is this 1lb of wood contains X amount of energy. We can compare the amount of energy that the wood contains to the amount of energy that is released into the living space as heat. That ratio should be consistent no matter what amount of wood is burned (assuming that the unit is at operating temperature) So really regardless of BTU output claims the manufacturer makes the ratio should be consistent and therefore the overall efficiency # should be fairly accurate. So with our overall efficency number we can then take the common species of wood in our area and figure out how many btu's per pound it has and how many pounds of it can be stuffed into the fireboxes of the stoves being compared. With that information a reasonable BTU output # should be reached right? So as long as the stove company did not blatantly lie about the amount of heat the stove put out compared to the amount of heat the load of wood theoretically contained we should be able to rely on that number.
Here's an example of what I mean

Vermont Castings Non-Cat Defiant 3.4 cubic ft. firebox with a 70% overall efficency claimed btu output of 60,000 btu.
Lopi Liberty Non-Cat 3.1 cubic ft. firebox with a 70% overall efficency claimed btu output of 74,300 btu.

The wood I am going to burn contains 6000 btu's per pound and 1 lb. of wood occupies .25 cubic ft.
For the VC theoretically I should be able to get 3.4 cubic ft. of wood in the firebox. That's 81,600 BTU of input. At 70% efficiency I should be able to expect a BTU output from this stove of 57,120 BTU
For the Lopi theoretically I should be able to get 3.1 cubic ft. of wood in the firebox. That's 74,400 BTU of input. At 70% efficency I should be able to expect a BTU output from this stove of 52,080 BTU.
Basically these two stoves are the same even though there is a 15,000 btu gap in the BTU output claims.

I think the large discrepancy between the Manufacturers claims is in the rate at which wood is consumed. They always say BTU's per hour and it should be BTU's per pound of wood at a certain moisture content. And in my opinion should test a list of 5-10 species.

Elk, Vogelzang is technically not false advertising. You do have to read between the lines with their statements but that is not false advertising. It's not a blatant misrepresentation of the truth. They are meeting all EPA requirements, the fact that the EPA has no requirements for those stoves is another issue. Even the use of the word "exceeds" is not really misleading as any efficiency that those "death boxes" manage to get is in excess of the EPA requirement. It is a loophole in the EPA requirements that should be addressed. They should require more specific verbage by companies producing stoves that are exempt. And quite honestly they shouldn't be allowed to produce them.
 
precaud said:
Webmaster said:
The hang tags and tests mean little because:
a. Oven dried fir firebrands so not burn like 20% moisture oak.
b. Many stoves are designed with passing the tests in mind, sometimes even at the expense or real world use.
c. Operator, chimney, fuel and altitude variables still exist.
<snip>

In general, I don't disagree with what you're written. But I will add my experience with 5 stoves installed this past burning season (three in my home, two in friends' homes).

For those of us 'condemned' to burn softwoods, the test reults for heat output range as printed on the EPA tag correlate quite well with the stove's performance we experienced - much better than manufacturer's claims and recommendations. In fact, of these five, the two stoves that performed the worst were the ones that had the greatest discrepancy between the manufacturers advertised max. heat output and the EPA test result. It can vary by a factor of two or more!

So, for softwood burners, I say, pay attention to the EPA tag results.

A list with specs of all stoves certified thru June 5005 at: http://www.state.nj.us/dep/airworkgroups/docs/certifiedwood.pdf


Notice most non cat stoves tested out at 63%, and cat stoves tested at 72%. The emissions were also lower on the cats on average. I guess cat stoves win!
 
cat stoves win for more efficiency and more possible user error, they also win for having planned obsolecent parts like catalysts, the also win for more user involvment then non cat stoves. Not everyone wants to watch there stove and rememeber to engage the catalyst, or worse engage it early and plug it. They both exist because there are differnt kind of folks out there that want stoves for different reasons, thats why there is so much out there on the market. Steel soapstone cast iron 8 inch flus 6 inch flues ash pans and non ash pans, cats and non cats. no one will argue that cats are a little more efficinet, just at what cost do they achieve that. Differnt strokes for different folks.
 
They are not required to publish measured efficiency specs, so they don't. Those figures are predetermined plugs.
 
Cat stoves win the aniti pollution issues less grams of pollutantes emitted. They have less forgiving draft requirements
can't be used effectively in a 12/12 direct connect masonry flue. Stove dealers delight extra service calls and replacements.
Now that aftermarket replacements out preform OEM ones at 50% cost. they l continue to light off at 360 degrees OEM 500. Not found in Zolegzang stoves. Hell the cat would be worth the price of the stove
more complete burn less cresote build up. Cost of cat replacement vs disentergrated secondary air tubes? Harder to use?
No harder the doing the same as anyone dampering down, the same lever is used? Are they for every customer (msg) no Unfortunately there are no idiot proof wood stoves that run by themselves, only Idiots who buy non listed stoves buy mail order
Do not fear MSG you were never in the running for those customers. How many $99 black boxes do you have?
Did you know there is no written warranty in the owner's manual.
more cautions in the instructions
OPERATING SAFETY PRECAUTIONS

1. Never overfire this stove by building excessively hot fires as a house/building fire may result. you are overfiring the stove If stove or stovepipe begins to glow or turn red.

2. Never build extremely large fires in this type of stove as damage to the stove or smoke leakage may result.
How the hell can they claim 200,000 BTU's if we can't get them cherry red and have to have small fires
A fire in the stove may be smothered by pouring a large quantity of coarse salt, baking soda, or cool ashes on top of the fire.
( and we thought rock salt was for icy walkways)

STOVE JOINTS: Required Tune-up.
This stove is manufactured with cast iron components. It does not have welded seams. Periodic "tune up" may be required by refilling and/or replacing the cement/joint mortar along the seams where the cast iron components meet.

What no warranty now suggesting periodic "tune up" after 6 months use?
 
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